[MIS25-P09] 安定同位体測定を用いた淡水生物寄生虫類の宿主ー寄生関係の解明
There are ubiquity of parasites all ecosystems, and it is said that they account for more than half of the species on earth. In Lake Biwa, more than 100 species of parasites have been reported, including trematoda, cestoda, acanthocephalans, and crustaceans. These parasites cause behavioral changes and trait changes in the host, directly and indirectly affecting the food web structure and material cycle of ecosystems. Stable carbon and nitrogen isotope measurement is widely used as a method to elucidate the material cycle and food web of ecosystems. It is known that the stable isotope ratio between carbon and nitrogen is enriched as the trophic level increases in the predator-prey relationship. On the other hand, it is suggested that the “host-parasite” relationship may be different from the conventional “predator-prey” relationship, even though the host is used as a resource.
Therefore we will measure the trophic relationship between parasites and host organisms using stable isotopes to elucidate the trophic level of parasites.
Cyprinid fish collected in Lake Biwa were dissected, and parasites were collected from the oral cavity, gills, swimwear, and digestive tract. The gills, swimwear, digestive tract, and muscle were removed from the host. All samples were lyophilized, powdered and measured. The measurement was performed using EA / IRMS, and Δ13C and Δ15N of the sample were measured. In addition, EA-IRMS was partially modified to measure microparasites one.
Crustaceans, monogenea, trematoda (larvae, adults), and acanthocephalans were found in Opsariichthys uncirostris. Δ13C and δ15N of the collected crustaceans, trematoda and acanthocephalans were measured. All the measured parasites showed negative values in Δ13C and Δ15N. We discuss these results.
Therefore we will measure the trophic relationship between parasites and host organisms using stable isotopes to elucidate the trophic level of parasites.
Cyprinid fish collected in Lake Biwa were dissected, and parasites were collected from the oral cavity, gills, swimwear, and digestive tract. The gills, swimwear, digestive tract, and muscle were removed from the host. All samples were lyophilized, powdered and measured. The measurement was performed using EA / IRMS, and Δ13C and Δ15N of the sample were measured. In addition, EA-IRMS was partially modified to measure microparasites one.
Crustaceans, monogenea, trematoda (larvae, adults), and acanthocephalans were found in Opsariichthys uncirostris. Δ13C and δ15N of the collected crustaceans, trematoda and acanthocephalans were measured. All the measured parasites showed negative values in Δ13C and Δ15N. We discuss these results.